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10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
Constraining the evolution of the fundamental constants with a solid-state optical frequency reference based on the
Wade G Rellergert1, D DeMille, R R Greco
1Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA.
Physical Review Letters
|September 28, 2010
Summary
Researchers propose a new method to measure the energy of the Thorium-229 (229Th) isomeric state. This approach could lead to a highly stable solid-state optical frequency reference and better tests of fundamental constants.
Area of Science:
- Nuclear Physics
- Quantum Optics
- Metrology
Background:
- The low-lying isomeric state in Thorium-229 (229Th) is of significant interest due to its potential for precision measurements.
- Directly measuring the energy of this nuclear state is challenging but crucial for applications in metrology and fundamental physics.
Purpose of the Study:
- To present a novel approach for directly measuring the energy of the 229Th narrow, low-lying isomeric state.
- To explore the feasibility of using the 229Th optical nuclear transition within a host crystal for advanced applications.
Main Methods:
- Proposing to drive the 229Th optical nuclear transition inside a host crystal with a high transition Q (quality factor).
- Analyzing the crystal lattice environment to predict achievable precision and accuracy.
Main Results:
- The proposed technique may enable the construction of a solid-state optical frequency reference with stability surpassing current optical clocks.
- A precision (short-term stability) of 3×10(-17)<Δf/f<1×10(-15) and systematic-limited accuracy (long-term stability) of Δf/f∼2×10(-16) are predicted.
- Potential for improving constraints on the variability of fundamental constants by 10(2)-10(3) is indicated.
Conclusions:
- The described method offers a promising pathway for precise measurement of the 229Th isomeric state energy.
- This technique could lead to next-generation optical clocks and enhanced tests of fundamental physical laws.
- The use of nuclear transitions in host crystals presents a viable route for advanced metrology.
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